Add 'names.ToCamelCase'.

names/camel.go

@@ -0,0 +1,63 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package names
+
+import (
+	"strings"
+)
+
+// toCamelCase converts a string to CamelCase.
+func toCamelCase(in string, initialCap bool) string {
+	out := strings.Builder{}
+
+	nextIsCap := initialCap
+	prevIsCap := false
+	for i, ch := range []byte(in) {
+		isCap := isCapitalLetter(ch)
+		isLow := isLowercaseLetter(ch)
+		isDig := isNumeric(ch)
+
+		if nextIsCap {
+			if isLow {
+				ch = toUppercaseLetter(ch)
+			}
+		} else if i == 0 {
+			if isCap {
+				ch = toLowercaseLetter(ch)
+			}
+		} else if prevIsCap && isCap {
+			ch = toLowercaseLetter(ch)
+		}
+
+		prevIsCap = isCap
+
+		if isCap || isLow {
+			out.WriteByte(ch)
+			nextIsCap = false
+		} else if isDig {
+			out.WriteByte(ch)
+			nextIsCap = true
+		} else {
+			nextIsCap = ch == '_' || ch == ' ' || ch == '-' || ch == '.'
+		}
+	}
+
+	return out.String()
+}
+
+func toUppercaseLetter(ch byte) byte {
+	ch += 'A'
+	ch -= 'a'
+	return ch
+}
+
+// ToCamelCase converts a string to CamelCase.
+func ToCamelCase(in string) string {
+	return toCamelCase(in, true)
+}
+
+// ToLowerCamelCase converts a string to camelCase.
+func ToLowerCamelCase(in string) string {
+	return toCamelCase(in, false)
+}

names/camel_test.go

@@ -0,0 +1,125 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package names
+
+import (
+	"testing"
+)
+
+func TestToCamelCase(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "empty",
+			input:    "",
+			expected: "",
+		},
+		{
+			name:     "All lower",
+			input:    "lower",
+			expected: "Lower",
+		},
+		{
+			name:     "Initial upper",
+			input:    "Lower",
+			expected: "Lower",
+		},
+		{
+			name:     "Two words",
+			input:    "Two words",
+			expected: "TwoWords",
+		},
+		{
+			name:     "Three words",
+			input:    "TheseThreeWords",
+			expected: "TheseThreeWords",
+		},
+		{
+			name:     "A long one",
+			input:    "global-Replication_Group.description",
+			expected: "GlobalReplicationGroupDescription",
+		},
+		{
+			name:     "Including a digit",
+			input:    "s3bucket",
+			expected: "S3Bucket",
+		},
+		{
+			name:     "Constant case",
+			input:    "CONSTANT_CASE",
+			expected: "ConstantCase",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			t.Parallel()
+
+			if got, want := ToCamelCase(testCase.input), testCase.expected; got != want {
+				t.Errorf("got: %s, expected: %s", got, want)
+			}
+		})
+	}
+}
+
+func TestToLowerCamelCase(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "empty",
+			input:    "",
+			expected: "",
+		},
+		{
+			name:     "All lower",
+			input:    "lower",
+			expected: "lower",
+		},
+		{
+			name:     "Initial upper",
+			input:    "Lower",
+			expected: "lower",
+		},
+		{
+			name:     "Two words",
+			input:    "Two words",
+			expected: "twoWords",
+		},
+		{
+			name:     "Three words",
+			input:    "TheseThreeWords",
+			expected: "theseThreeWords",
+		},
+		{
+			name:     "A long one",
+			input:    "global-Replication_Group.description",
+			expected: "globalReplicationGroupDescription",
+		},
+		{
+			name:     "Including a digit",
+			input:    "s3bucket",
+			expected: "s3Bucket",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			t.Parallel()
+
+			if got, want := ToLowerCamelCase(testCase.input), testCase.expected; got != want {
+				t.Errorf("got: %s, expected: %s", got, want)
+			}
+		})
+	}
+}

names/snake_test.go

@@ -60,6 +60,11 @@ func TestToSnakeCase(t *testing.T) {
 			input:    "ResourceARN",
 			expected: "resource_arn",
 		},
+		{
+			name:     "Resource-ARN",
+			input:    "Resource-ARN",
+			expected: "resource_arn",
+		},
 	}
 
 	for _, testCase := range testCases {